getHNFavorites.js

javascript:
/*
name: /HN Favorites#
url: https://github.com/gabrielsroka/gabrielsroka.github.io/blob/master/getHNFavorites.js

Search HN Favorites and Export to CSV or HTML.
It runs in your browser like a browser extension. It scrapes the HN HTML and navigates from page to page.

Setup:
Bookmark: Drag this to your bookmarks toolbar, or
Copy this code to the browser console or, if using Chrome, to a Snippet. For example:
1. Press F12 (Windows) to open DevTools.
2. Go to Sources > Snippets, click New Snippet.
3. Give it a name, eg, "HN Favorites".
4. Copy/paste the code from https://gabrielsroka.github.io/getHNFavorites.js
5. Save (Ctrl+S, Windows).

Usage:
Bookmark: Click the bookmark, or
1. Navigate your browser to https://news.ycombinator.com/user?id=YOUR_USER_ID
2. Press F12 (Windows) to open DevTools.
3. Run the code. If using a Snippet, there's a Run button on the bottom right, or press Ctrl+Enter (Windows).
4. Look for the popup window in the upper-left corner of your browser.
*/

(function () {
    const popup = createPopup('HN Favorites');
    if (location.host != 'news.ycombinator.com' || !(location.pathname == '/user' || location.pathname == '/favorites'))  {
        popup.innerHTML = 'ERROR: Go to your user or favorites page on HN and then try again.';
        return;
    }
    const id = location.search.split('=')[1];
    const types = {
        csv: {
            header: 'Name,URL',
            filename: id + "'s HN favorites",
            totype: f => toCSV(f.name, f.url)
        },
        html: {
            header: '<title>' + id + "'s HN favorites</title><style>body {font-family: sans-serif;}</style><h1>" + id + "'s HN favorites</h1>",
            filename: id + "'s-HN-favorites",
            totype: f => '<p>' + link(f.url, f.name)
        }
    };
    const favorites = [];
    const form = popup.appendChild(document.createElement('form'));
    form.innerHTML = 
        '<input id=query> <button type=submit>Search</button> ' + 
        'Export to <button id=exportToCSV data-filetype=csv>CSV</button> ' + 
        '<button id=exportToHTML data-filetype=html>HTML</button><br><br>' +
        '<div id=results></div>';
    query.focus();
    form.onsubmit = async function (event) {
        event.preventDefault();
        const re = new RegExp(query.value, 'i');
        await getFavorites();
        const found = favorites
            .filter(f => f.name.match(re) || f.url.match(re))
            .map(f => '<tr><td>' + link(f.url, f.name) + '<td>' + link(f.url, f.url));
        results.innerHTML = found.length ? '<table>' + found.join('') + '</table>' : 'not found';
    };
    exportToCSV.onclick = exportToHTML.onclick = async function (event) {
        event.preventDefault();
        const filetype = this.dataset.filetype;
        await getFavorites();
        downloadFile(types[filetype].header, favorites.map(types[filetype].totype), types[filetype].filename, filetype);
        results.innerHTML = 'Finished exporting.';
    };
    async function getFavorites() {
        if (favorites.length > 0) return;
        var url = `favorites?id=${id}`;
        var page = 1;
        while (url) {
            results.innerHTML = `Fetching page ${page++} ...<br><br>`;
            const response = await fetch(url);
            const html = await response.text();
            const parser = new DOMParser();
            const doc = parser.parseFromString(html, 'text/html');
            doc.querySelectorAll('span.titleline a').forEach(a => favorites.push({name: a.innerText, url: a.href}));
            const more = doc.querySelector('a.morelink');
            url = more?.href;
            if (more) {
                await sleep(850);
            }
        }
    }

    function createPopup(title) {
        const div = document.body.appendChild(document.createElement('div'));
        div.innerHTML = title + " <a onclick='document.body.removeChild(this.parentNode)' style='cursor: pointer; padding: 4px'>X</a><br><br>";
        div.style.cssText = 'position: absolute; padding: 8px; top: 4px; color: black; background-color: white; z-index: 1001; border: 1px solid #ddd;';
        return div.appendChild(document.createElement('div'));
    }
    function toCSV(...fields) {
        return fields.map(field => `"${field == undefined ? "" : field.toString().replace(/"/g, '""')}"`).join(',');
    }
    function downloadFile(header, lines, filename, filetype) {
        const a = document.body.appendChild(document.createElement('a'));
        a.href = URL.createObjectURL(new Blob([header + '\n' + lines.join('\n')], {type: 'text/' + filetype}));
        const date = new Date().toISOString().replace(/[T:]/g, '-').slice(0, 19);
        a.download = `${filename}-${date}.${filetype}`;
        a.click();
    }
    async function sleep(time) {
        return new Promise(resolve => setTimeout(resolve, time));
    }
    function link(url, text) {
        return `<a href="${url}" target=_blank>${text}</a>`;
    }
})();